《Big History》_1

Big history and the Big Bang

Knowing the names and dates of history is important, but we just can't do that in Big History. There are much broader historical questions in the stories of the universe that can only be explored by zooming out to the ultimate scale. As you zoom out, you see a lot of the picture, and the details get more fuzzy.

The universe is very old, 13.8 billion years old. If we compress it to 13 years, small enough that our puny brain can handle it. On that timescale, the universe have begun 13 years ago. The first star and galaxies would form 12 years ago(?). About 4.5 years ago, the Earth would formed. Move a bit up to 4 years ago, that when the first single celled life formed on Earth. Then leap forward nearly 3.5 years, the first multi-cellular life. The first homo sapiens emerged 50 minutes ago. We invented the agriculture 5 minutes ago...

To my surprise, theoretical physicist said that the space-time are created by the Big Bang. Thus time didn't exist before the Big Bang. It expanded form an unimaginably small tiny point, to an unimaginably large universe unimaginably quickly.